A starting point

Oswald the Lucky Rabbit www.wikipedia.org

  On September 5, 1927 the short film "Oswald the Lucky Rabbit" in "Trolley Troubles".  This short was produced by Walt Disney and Ub Iwerks and released by Universal Studios.
  The was the "official" start of a career for Walt Disney which, as we all know, exploded and his work has become a standard by which others are judged.
  Oswald is still around, though not seen much.  Disney Studios and Universal both claimed ownership and at one point it was an exclusive Universal property.  It was passed back to Disney by some agreement.
  Oswald was also seen as a comic book series drawn by Walter Lanz (think Woody Woodpecker), but had a short run.
  So everyone starts somewhere, in the case the career of Walt Disney.

"Africa Before Dark" another release in 1927  www.wikipedia.org